TimeSlice

Timeslice (aka “bullet time“) is a technique pioneered by Tim Macmillan and later made famous by movies like the Matrix. Ever since consumer digital cameras have dropped in price I have become interested in attempting this technique. Consistent alignment and spacing of the cameras is key. Below is a test using 5 GoPro cameras. I am syncing these all up manually in post with a film slate. My recent discovery of PluralEyes will help speed up this initial post process.

I am shooting all of these on GoPro Heros at 720 60fps and using twixtor for super slow motion effect. Christopher Kaczmarzyk, a member of my GoPro NYC meetup group, machined some prototype mounts for me to thread 1/4″ – 20 bolts to help mount the cameras consistently. The goal of this project is to produce the best quality timeslice footage on a super portable rig with very little money.

Jeff Campbell at Ambarella (the company responsible for the imaging chip inside GoPro cameras) has been nice enough to send me a few cameras for my experiments. Ideally you will want to use the same cameras for something like this. In addition to the Hero2’s improved image quality, its white balance and exposure will differ and will not match the other models. I would prefer all Hero2’s but I suppose that will have to wait

This is my first test. I mounted 4 GoPro cameras to the hood of a car.

This next test spaces the cameras roughly 6″ apart (no audio).
(Don’t worry, no animals were harmed during this shoot)

These tests space the cameras roughly 12″ apart. The difference is obvious.

Here are 5 GoPro Hero Hd Cameras mounted to a custom cut piece of particle board. The cameras are hooked up to a 4.5″ LCD screen for monitoring. GoPro LCD bac pacs would drain too much battery, increase the cost and most importantly not be as advantageous as seeing all of the shots in succession on one screen.

Using analog Sony A/V switches to route all cameras to a single monitor I am able to turn the knobs to flip through the cameras on the monitor. Essentially getting a real time read of the effect. It’s not smooth or perfect but it’s good enough for now. The HERO2 has an HDMI out so I suspect that a digital solution can be very smooth.

All cameras can be monitored, tested and eyeballed with this LCD screen.

I think the biggest issue I have with using GoPro Hero cameras with this is their super wide angle. I would like to try this with a set of Hero2’s so that I can shoot in “narrow” mode.

Here is a really interesting clip that shows Tim Macmillan’s early creations and how he did it with film. You can see some more of Macmillan and crew’s work at TimeSliceFilms.com

Pretty neat!

Macmillan with a LOT of GoPros

Here is another interesting method that a company called The Marmalade uses. It’s a Phantom HD camera attached to an industrial robotic arm. Because the frame rate is so high and the movement so fast the results are pretty amazing:

And finally, here’s a low budget version of the above example that uses a GoPro and a fan motor:

Post production is definitely the roadblock here. Since we don’t have the resources to build custom software to process these shots we have to do this manually. I was thinking of adding my post process to another post. I’m using Premiere Pro CS5 but the concept is the same in any application. After Effects might actually be too complex for this, but I could be wrong.

Aside from aligning cameras as evenly as possible you definitely want to slate(clapper) the shot before your action. You can also just clap with your hands. Having the audio and visual cue will help line the shots up. In a nutshell what I do is line up the clips on top of one another and use the ‘hold on frame’ option for the clips. Then I manually nudge each clip further in time so I am left with a staircase/pyramid-like pattern. This is pretty time consuming but pretty satisfying if the shot was done well.

In addition to the automated software the pros are using I believe they are also using software to interpolate frames as well to further smooth it out.